Field of The Invention
The present invention relates to a filter device for removing leukocytes. More particularly, the present invention is concerned with a leukocyte-removing filter device comprising (a) a casing having an inlet for blood and an outlet for leukocyte-removed blood, which are both located in a top portion of the casing, and (b) a filter medium disposed in the casing so as to divide the internal space of the casing into an inlet-side chamber communicated with the inlet and an outlet-side chamber communicated with the outlet. By virtue of the specific locations of the inlet and outlet of the filter device, the leukocyte-removing filter device of the present invention is advantageous not only in that the filter device can be fittedly and stably accommodated in a centrifuge cup together with a plurality of blood bags and circuit tubes connecting the filter device and blood bags, so that a centrifugation can be efficiently conducted without the danger of damaging the filter device and the blood bags, but also in that the operation of expelling the air from the filter by filling the filter with blood can be very readily performed simply by allowing blood to flow into the filter without any additional burdensome operations. In addition, this filter is simple in structure and, therefore, is easy to produce. The present invention is also concerned with a leukocyte-removing system comprising this novel leukocyte-removing filter device, inlet connecting means fluid-tightly connected to the inlet of the filter device for aseptically connecting a part preceding the filter device to the inlet of the filter device, and outlet connecting means for connecting the outlet of the filter device to at least one blood bag.